Which statement was a factor in there decline of sumer

The statements that were a factor in the decline of Sumer are the following:

The cultivated soil had poor drainage  

Salinization of the soil occurred

Nomads invaded Sumerian city-states

Sumer was ancient Mesopotamia’s southernmost territory and is believed to be the cradle of civilization.

yes

explanation:

the fighting words doctrine, in united states constitutional law, is a limitation to freedom of speech as protected by the first amendment to the united states constitution. in 1942, the u.s. supreme court established the doctrine by a 9–0 decision in chaplinsky v. new hampshire.

the name of the theory is landmass theory.